X-ray therapy for acute pancreatitis

Preoperative chemoradiation reduces the risk of pancreatic fistula after distal pancreatectomy for pancreatic adenocarcinoma

BACKGROUND

Pancreatic fistula (PF) is a common complication after pancreatectomy. Previous reports indicate that preoperative irradiation decreases the risk of PF after pancreatoduodenectomy. In this context, the impact of preoperative chemoradiation therapy (CRT) on PF formation after distal pancreatectomy is of interest.

METHODS

Fifty-eight patients with pancreatic adenocarcinoma who underwent distal pancreatectomy, including 28 patients with preoperative gemcitabine-based CRT and 30 patients without preoperative treatment, were assessed in this study. The incidence and severity of postoperative PF, assessed according to the definition of the International Study Group on Pancreatic Fistula, were compared between the 2 groups.

RESULTS

In the CRT group, 86% of patients did not develop PF, whereas grades A and B PF were observed in 1 and 3 patients, respectively. In the non-CRT group, 33% of patients did not develop a PF, whereas grades A and B PF were observed in 9 and 11 patients, respectively. The incidence of clinically significant PF, defined as either grade B or grade C PF, was less in the CRT group (P = .031). The amylase activities in the draining fluid on postoperative days 1 and 3 were both less in the CRT group (P = .003 and P = .006, respectively).

CONCLUSION

Preoperative CRT significantly decreases the incidence of PF after distal pancreatectomy, which potentially provides another benefit to patients in addition to its original advantages (ie, locoregional effect and patient selection effect), allowing more opportunities for the immediate initiation of postoperative adjuvant treatment.

[Radiation therapy of chronic pancreatitis. Case report]

BACKGROUND

Chronic pancreatitis is a severe inflammatory process leading to destruction of exocrine tissue, fibrosis and a sometimes fatal pancreatic necrosis. Therapeutic options are poor and restricted to an exclusively symptomatic treatment. In this situation any additional treatment option is welcome.

CASE REPORT

The present paper reports the successful irradiation of a patient with severe chronic pancreatitis resistant to any pretreatment. Pain relief was stated one week after beginning of the irradiation. Total dose was 7 Gy, applied with opposing ap/pa fields using 8 MV photons. Three years after treatment the patient has remained free from symptoms. He has gained 14 kg of weight and is working regularly.

Abdominal radiotherapy is a cause for chronic pancreatitis

We report a series of five patients with nonalcoholic chronic pancreatitis who underwent abdominal radiotherapy for Hodgkin's disease (n = 4) or seminoma (n = 1) at doses ranging from 3600 to 4050 rads, 6 to 20 years (median, 7 years) before the onset of pancreatitis. Patients were in complete remission for their malignant disease. Other causes of chronic pancreatitis were excluded. The manifestations of chronic pancreatitis (median follow-up after the diagnosis of pancreatitis, 5 years) were pancreatic pain (n = 5), acute pancreatitis (n = 3), pseudocysts (n = 3), common bile duct stenosis (n = 2), duodenal stenosis (n = 1), splenic vein obstruction (n = 1), diabetes mellitus (n = 4), steatorrhea (n = 4), and pancreatic calcifications (n = 1). Other abdominal radiation injuries were severe chronic ulcer of the genu superius (n = 1), stenosis at the junction of the right and left hepatic ducts (n = 1), and splenic and left renal atrophy (n = 1). In one patient, pathological examination of the pancreas showed signs of chronic pancreatitis, severe fibrous endarteritis, and lack of inflammation. Abdominal radiotherapy should be added to the list of causes of chronic pancreatitis. We suggest that the physiopathology of postradiotherapy chronic pancreatitis is a vascular process.

Exocrine pancreatic function following intraoperative irradiation of the canine pancreas

Twenty-four beagles received intraoperative irradiation (IORT) with 6 meV electrons to the pancreas and the duodenum. Intraoperative irradiation doses of 17.5 to 40 Gy were given. Billroth II gastrojejunostomy was done to bypass the irradiated duodenum. Six control dogs received only the Billroth II surgery. Two weeks postoperatively, irradiated dogs were given 50 Gy of 6 MV X radiation (external-beam radiation [EBRT]) to the pancreas and duodenum in 2 Gy fractions over a 5-week period. Dogs were monitored clinically and exocrine pancreatic function was evaluated using an N-benzoyl-l-tyrosyl-para-aminobenzoic acid (BT-PABA) test between 3 and 135 days postoperatively. Necropsies were performed on the dogs at 135 days postoperatively. The degree of gross pancreatic atrophy in the irradiated group was dose related. The mean percentage of normal acinar cells correlated with IORT doses and para-aminobenzoic acid (PABA) values (P less than 0.1). Weight loss was significantly greater in the irradiated dogs compared to the control (P less than 0.05) and the mean percentage of body weight loss correlated with the mean PABA values (P less than 0.01). In this study, the use of the BT-PABA test to evaluate progressive exocrine pancreatic function following IORT and EBRT showed an expected trend. A progressive decrease in exocrine pancreatic function in the irradiated dogs as indicated by plasma PABA levels may have been partly due to late radiation damage to acinar cells, secondary to vascular and ductular damage. At 135 days postoperatively none of the dogs showed clinical signs of exocrine pancreatic insufficiency and the plasma PABA levels were within the normal presurgical range. The progressive decrease in plasma PABA levels indicated a potential for the late development of exocrine pancreatic insufficiency. The BT-PABA test could be useful for evaluating the progressive decrease in exocrine pancreatic function and residual radiation injury to the pancreas. Because the exocrine deficiency can be managed with replacement therapy, pancreatic injury may not be a serious complication after doses of less than 30 Gy IORT with 50 Gy EBRT. Data from this study are in agreement with previous clinical and experimental reports that the duodenum is dose-limiting for IORT. Doses of 20 Gy IORT or less plus 50 Gy EBRT for treatment of carcinoma of the pancreas may not result in serious long-term complications due to radiation injury of the duodenum.

Pancreatic insufficiency following abdominal irradiation

A case is reported of pancreatic insufficiency following abdominal irradiation for Hodgkin's disease in a man aged 47 years. The effects of radiation on the pancreas are discussed. It is suggested that post irradiation steatorrhoea may have a pancreatic as well as an enteric cause.

Pancreatic ascites: successful treatment with pancreatic radiation

A 51-year-old man with clinical and laboratory findings consistent with the diagnosis of pancreatic ascites is reported. Response to usual medical measures was inadequate. Single-dose irradiation to the pancreatic area (550 rads) resulted in marked improvement in his ascites. Operative pancreatogram months later revealed no evidence of ductal leakage. Low-dose pancreatic irradiation may be a unseful therapeutic adjunct in the older, high-risk patient with pancreatic ascites in whom surgery is not considered feasible.